package fr.gdi.android.news.activity;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.TreeMap;

import android.app.AlertDialog;
import android.app.ListActivity;
import android.content.DialogInterface;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.inputmethod.InputMethodManager;
import android.widget.Button;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.widget.SimpleAdapter;
import android.widget.TextView;
import fr.gdi.android.news.R;

/**
 * Activity para escolha de arquivos/diretorios.
 * 
 * @author android
 * 
 */
public class FilePickerActivity extends ListActivity
{
    
    public static class SelectionMode
    {
        public static final int MODE_CREATE = 0;
        public static final int MODE_OPEN = 1;
    }
    
    /**
     * Chave de um item da lista de paths.
     */
    private static final String ITEM_KEY = "key"; //$NON-NLS-1$
    
    /**
     * Imagem de um item da lista de paths (diretorio ou arquivo).
     */
    private static final String ITEM_IMAGE = "image"; //$NON-NLS-1$
    
    /**
     * Diretorio raiz.
     */
    private static final String ROOT = "/"; //$NON-NLS-1$
    
    /**
     * Parametro de entrada da Activity: path inicial. Padrao: ROOT.
     */
    public static final String START_PATH = "START_PATH"; //$NON-NLS-1$
    
    /**
     * Parametro de entrada da Activity: filtro de formatos de arquivos. Padrao:
     * null.
     */
    public static final String FORMAT_FILTER = "FORMAT_FILTER"; //$NON-NLS-1$
    
    /**
     * Parametro de saida da Activity: path escolhido. Padrao: null.
     */
    public static final String RESULT_PATH = "RESULT_PATH"; //$NON-NLS-1$
    
    /**
     * Parametro de entrada da Activity: tipo de selecao: pode criar novos paths
     * ou nao. Padrao: nao permite.
     * 
     * @see {@link SelectionMode}
     */
    public static final String SELECTION_MODE = "SELECTION_MODE"; //$NON-NLS-1$
    
    /**
     * Parametro de entrada da Activity: se e permitido escolher diretorios.
     * Padrao: falso.
     */
    public static final String CAN_SELECT_DIR = "CAN_SELECT_DIR"; //$NON-NLS-1$
    
    private List<String> path = null;
    private TextView myPath;
    private EditText mFileName;
    private ArrayList<HashMap<String, Object>> mList;
    
    private Button selectButton;
    
    private LinearLayout layoutSelect;
    private LinearLayout layoutCreate;
    private InputMethodManager inputManager;
    private String parentPath;
    private String currentPath = ROOT;
    
    private int selectionMode = SelectionMode.MODE_CREATE;
    
    private String[] formatFilter = null;
    
    private boolean canSelectDir = false;
    
    private File selectedFile;
    private HashMap<String, Integer> lastPositions = new HashMap<String, Integer>();
    
    /**
     * Called when the activity is first created. Configura todos os parametros
     * de entrada e das VIEWS..
     */
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setResult(RESULT_CANCELED, getIntent());
        
        setContentView(R.layout.file_dialog_main);
        myPath = (TextView) findViewById(R.id.path);
        mFileName = (EditText) findViewById(R.id.fdEditTextFile);
        
        inputManager = (InputMethodManager) getSystemService(INPUT_METHOD_SERVICE);
        
        selectButton = (Button) findViewById(R.id.fdButtonSelect);
        selectButton.setEnabled(false);
        selectButton.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v)
            {
                if (selectedFile != null)
                {
                    getIntent().putExtra(RESULT_PATH, selectedFile.getPath());
                    setResult(RESULT_OK, getIntent());
                    finish();
                }
            }
        });
        
        final Button newButton = (Button) findViewById(R.id.fdButtonNew);
        newButton.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v)
            {
                setCreateVisible(v);
                
                mFileName.setText(""); //$NON-NLS-1$
                mFileName.requestFocus();
            }
        });
        
        selectionMode = getIntent().getIntExtra(SELECTION_MODE, SelectionMode.MODE_CREATE);
        
        formatFilter = getIntent().getStringArrayExtra(FORMAT_FILTER);
        
        canSelectDir = getIntent().getBooleanExtra(CAN_SELECT_DIR, false);
        
        if (selectionMode == SelectionMode.MODE_OPEN)
        {
            newButton.setEnabled(false);
        }
        
        layoutSelect = (LinearLayout) findViewById(R.id.fdLinearLayoutSelect);
        layoutCreate = (LinearLayout) findViewById(R.id.fdLinearLayoutCreate);
        layoutCreate.setVisibility(View.GONE);
        
        final Button cancelButton = (Button) findViewById(R.id.fdButtonCancel);
        cancelButton.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v)
            {
                setSelectVisible(v);
            }
            
        });
        final Button createButton = (Button) findViewById(R.id.fdButtonCreate);
        createButton.setOnClickListener(new OnClickListener() {
            
            @Override
            public void onClick(View v)
            {
                if (mFileName.getText().length() > 0)
                {
                    getIntent().putExtra(RESULT_PATH, currentPath + "/" + mFileName.getText()); //$NON-NLS-1$
                    setResult(RESULT_OK, getIntent());
                    finish();
                }
            }
        });
        
        String startPath = getIntent().getStringExtra(START_PATH);
        startPath = startPath != null ? startPath : ROOT;
        if (canSelectDir)
        {
            File file = new File(startPath);
            selectedFile = file;
            selectButton.setEnabled(true);
        }
        getDir(startPath);
    }
    
    private void getDir(String dirPath)
    {
        
        boolean useAutoSelection = dirPath.length() < currentPath.length();
        
        Integer position = lastPositions.get(parentPath);
        
        getDirImpl(dirPath);
        
        if (position != null && useAutoSelection)
        {
            getListView().setSelection(position);
        }
        
    }
    
    /**
     * Monta a estrutura de arquivos e diretorios filhos do diretorio fornecido.
     * 
     * @param dirPath
     *            Diretorio pai.
     */
    private void getDirImpl(final String dirPath)
    {
        
        currentPath = dirPath;
        
        final List<String> item = new ArrayList<String>();
        path = new ArrayList<String>();
        mList = new ArrayList<HashMap<String, Object>>();
        
        File f = new File(currentPath);
        File[] files = f.listFiles();
        if (files == null)
        {
            currentPath = ROOT;
            f = new File(currentPath);
            files = f.listFiles();
        }
        myPath.setText(getText(R.string.location) + ": " + currentPath); //$NON-NLS-1$
        
        if (!currentPath.equals(ROOT))
        {
            
            item.add(ROOT);
            addItem(ROOT, R.drawable.folder);
            path.add(ROOT);
            
            item.add("../"); //$NON-NLS-1$
            addItem("../", R.drawable.folder); //$NON-NLS-1$
            path.add(f.getParent());
            parentPath = f.getParent();
            
        }
        
        TreeMap<String, String> dirsMap = new TreeMap<String, String>();
        TreeMap<String, String> dirsPathMap = new TreeMap<String, String>();
        TreeMap<String, String> filesMap = new TreeMap<String, String>();
        TreeMap<String, String> filesPathMap = new TreeMap<String, String>();
        for (File file : files)
        {
            if (file.isDirectory())
            {
                String dirName = file.getName();
                dirsMap.put(dirName, dirName);
                dirsPathMap.put(dirName, file.getPath());
            }
            else
            {
                final String fileName = file.getName();
                final String fileNameLwr = fileName.toLowerCase();
                // se ha um filtro de formatos, utiliza-o
                if (formatFilter != null)
                {
                    boolean contains = false;
                    for (int i = 0; i < formatFilter.length; i++)
                    {
                        final String formatLwr = formatFilter[i].toLowerCase();
                        if (fileNameLwr.endsWith(formatLwr))
                        {
                            contains = true;
                            break;
                        }
                    }
                    if (contains)
                    {
                        filesMap.put(fileName, fileName);
                        filesPathMap.put(fileName, file.getPath());
                    }
                    // senao, adiciona todos os arquivos
                }
                else
                {
                    filesMap.put(fileName, fileName);
                    filesPathMap.put(fileName, file.getPath());
                }
            }
        }
        item.addAll(dirsMap.tailMap("").values()); //$NON-NLS-1$
        item.addAll(filesMap.tailMap("").values()); //$NON-NLS-1$
        path.addAll(dirsPathMap.tailMap("").values()); //$NON-NLS-1$
        path.addAll(filesPathMap.tailMap("").values()); //$NON-NLS-1$
        
        SimpleAdapter fileList = new SimpleAdapter(this, mList, R.layout.file_dialog_row, new String[] { ITEM_KEY, ITEM_IMAGE }, new int[] { R.id.fdrowtext,
                R.id.fdrowimage });
        
        for (String dir : dirsMap.tailMap("").values()) //$NON-NLS-1$
        {
            addItem(dir, R.drawable.folder);
        }
        
        for (String file : filesMap.tailMap("").values()) //$NON-NLS-1$
        {
            addItem(file, R.drawable.file);
        }
        
        fileList.notifyDataSetChanged();
        
        setListAdapter(fileList);
        
    }
    
    private void addItem(String fileName, int imageId)
    {
        HashMap<String, Object> item = new HashMap<String, Object>();
        item.put(ITEM_KEY, fileName);
        item.put(ITEM_IMAGE, imageId);
        mList.add(item);
    }
    
    /**
     * Quando clica no item da lista, deve-se: 1) Se for diretorio, abre seus
     * arquivos filhos; 2) Se puder escolher diretorio, define-o como sendo o
     * path escolhido. 3) Se for arquivo, define-o como path escolhido. 4) Ativa
     * botao de selecao.
     */
    @Override
    protected void onListItemClick(ListView l, View v, int position, long id)
    {
        
        File file = new File(path.get(position));
        
        setSelectVisible(v);
        
        if (file.isDirectory())
        {
            selectButton.setEnabled(false);
            if (file.canRead())
            {
                lastPositions.put(currentPath, position);
                getDir(path.get(position));
                if (canSelectDir)
                {
                    selectedFile = file;
                    v.setSelected(true);
                    selectButton.setEnabled(true);
                }
            }
            else
            {
                new AlertDialog.Builder(this).setIcon(R.drawable.icon).setTitle("[" + file.getName() + "] " + getText(R.string.cant_read_folder)) //$NON-NLS-1$ //$NON-NLS-2$
                        .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener() {
                            
                            @Override
                            public void onClick(DialogInterface dialog, int which)
                            {
                                
                            }
                        }).show();
            }
        }
        else
        {
            selectedFile = file;
            v.setSelected(true);
            selectButton.setEnabled(true);
        }
    }
    
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event)
    {
        if ((keyCode == KeyEvent.KEYCODE_BACK))
        {
            selectButton.setEnabled(false);
            
            if (layoutCreate.getVisibility() == View.VISIBLE)
            {
                layoutCreate.setVisibility(View.GONE);
                layoutSelect.setVisibility(View.VISIBLE);
            }
            else
            {
                if (!currentPath.equals(ROOT))
                {
                    getDir(parentPath);
                }
                else
                {
                    return super.onKeyDown(keyCode, event);
                }
            }
            
            return true;
        }
        else
        {
            return super.onKeyDown(keyCode, event);
        }
    }
    
    /**
     * Define se o botao de CREATE e visivel.
     * 
     * @param v
     */
    private void setCreateVisible(View v)
    {
        layoutCreate.setVisibility(View.VISIBLE);
        layoutSelect.setVisibility(View.GONE);
        
        inputManager.hideSoftInputFromWindow(v.getWindowToken(), 0);
        selectButton.setEnabled(false);
    }
    
    /**
     * Define se o botao de SELECT e visivel.
     * 
     * @param v
     */
    private void setSelectVisible(View v)
    {
        layoutCreate.setVisibility(View.GONE);
        layoutSelect.setVisibility(View.VISIBLE);
        
        inputManager.hideSoftInputFromWindow(v.getWindowToken(), 0);
        selectButton.setEnabled(false);
    }
}
